You have probably seen that there are plenty of lenses out there for Nikon DSLRs and you may be wondering what you need to know about DX and FX lenses.
It’s important to know the differences so you can make an educated purchase – read this post so you know what to consider.
What Are FX Lenses?
You won’t be the first person to ask what FX means when it comes to Nikon cameras.
In the Nikon camera system, the FX abbreviation signifies that the camera is a full frame camera and FX lenses are made for these full frame FX format cameras.
FX cameras have full frame sized sensors which are approximately 36mm x 24mm in size.
An example of an FX lens is the Nikon AF-S FX NIKKOR 17-35mm f/2.8D IF-ED
What Are DX Lenses?
DX lenses in Nikon’s range are lenses that are made for Nikon DX cameras which are all crop sensor cameras.
DX cameras have sensors which are approximately 24mm by 16mm in size so they are about 2/3rd’s the size of a full frame FX sensor.
This reduction in size allows for smaller and more affordable cameras and lenses compared to FX cameras and lenses.
An example of a DX lens is the Nikon AF-P DX NIKKOR 10-20mm f/4.5-5.6G VR.
Which Is Better – DX Or FX?
If you are comparing them strictly on a technical basis then FX is better than DX.
FX cameras have larger sensors with better low light capabilities and less noise.
In general, these cameras also tend to have more sturdy and expensive bodies as they cater towards professional photographers.
The FX lenses will also be of higher quality compared to DX lenses.
HOWEVER, FX will always be more expensive than DX so FX may not always be the best option for all people, especially if you are on a budget.
What Type Of Lens Will Fit My Nikon DSLR Camera?
What Cameras Will Fit A DX Lens?
Unlike the Canon system of lenses, you can use the crop sensor lenses on full frame cameras. So you can actually use DX lenses on FX format cameras.
The Nikon cameras will automatically compensate for the crop sensor lenses – this is the ‘auto DX crop’.
You can use any DX or FX Nikon camera with any DX lens.
What Cameras Will Fit An FX Lens?
You can use FX lenses on all FX format Nikon cameras and DX format cameras.
You may have seen information suggesting that you can’t use DX lenses on full frame FX cameras but this is not true.
Check out this post by Nikon themselves which states that you can indeed use a DX lens on a full frame FX camera.
Do The Lenses Affect The Crop Factor?
Yes and no. The thing that controls the crop factor is actually the sensor, but lets run through some scenarios as there is one special case:
DX sensor + DX or FX lens:
A DX sensor camera will have a crop factor of 1.5 applied, whatever lens you attach to it.
So a 24mm lens on a DX sensor will look more like a 36mm lens on a full frame.
FX camera with FX lens:
FX cameras have full frame sensors and the FX lens will not have a crop factor applied.
So a 24mm FX lens will have a field of view equal to a 24mm lens when attached to an FX camera.
FX camera with DX lens: (special case)
In the Canon family, you can’t use a crop sensor lens on a full frame camera without risking damage and a very strong vignette. However in the Nikon system, you can use a DX lens on a FX camera quite safely.
The camera will just automatically apply a crop to match the lens as the lenses have a smaller image circle.
So the camera will just take a smaller section of the full frame sensor and only portray the image from that subsection of the sensor. This works as a crop factor matching that of a DX sensor.
So a 24mm lens will have a 1.5 crop factor applied and will look like a 36mm lens full frame equivalent.
Why Should You Use A DX Lens?
An advantage of DX lenses is the option of true wide angle coverage that many of the lenses provide at a lower price point.
For example, consider the Nikon AF-P DX NIKKOR 10-20mm f/4.5-5.6G VR which has an equivalent focal length of 15-30mm.
But if you went for a full frame wide angle lens of a similar equivalent focal length it’s a completely different story!
The two lenses below are both FX lenses that fall into the wide angle range and cost WAY more than the DX lens above.
Of course it’s not just the focal length that matters and these FX lenses have much better maximum aperture capabilities meaning they are ‘faster’ lenses.
Also they can keep the aperture constant at f2.8 across the whole focal length range whereas the DX lens above ranges between f/4.5-5.6
You can see why people might choose an EF-S lens in this scenario if they are on a budget.
At the end of the day if you need a wide angle because of your subject and you don’t have cash to cough up then a DX will do you wonders.
An obvious scenario where they can be useful is in real estate photography when shooting indoors.
Things like the lower maximum aperture can be accounted for by using tripods and lower shutter speeds if you need more light in your scene.
How To Tell If A Nikon Lens Is DX Or FX
If you are using a Nikon branded Nikkor lens then they will clearly be marked with ‘DX’ somewhere on the lens barrel to show you that it is a DX lens which is made mainly for the DX cameras.
On the other hand, if Nikon made Nikkor Lens without DX on it then you can assume that it is a lens made for a FX format camera.
Strictly speaking there’s no such thing as a FX lens because it is just the standard for full frame. This is why they are not labelled as such.
How To Tell If A Third Party Lens Like Tamron Or Sigma Is Made For DX Or FX Format Camera?
Di lenses are made for full frame format cameras, so these would be equivalent to FX lenses.
Di-II lenses are made for APS-C crop sensor cameras so they would be the equivalent to DX lenses.
DG lenses are made for full frame format cameras, so these would be equivalent to FX lenses.
DC lenses are made for APS-C crop sensor cameras so they would be equivalent to DX lenses.
Compatibility of Third party lenses
Third party lenses can be a great choice as manufacturers like Tamron and Sigma are very reputable and often have more affordable lenses compared to the proprietary brands.
Just make sure that if you do get a third party lens that you ensure you are getting the right lens to match your camera as they make lenses for various manufacturers.
You don’t want to get a Tamron lens for a Canon camera when you have a Nikon!
So What Type Of Lens Shall I Buy For My Nikon DSLR Camera?
Match your lens to your needs.
If you have the budget for it, invest in full frame FX lenses whether you are on a crop sensor DX camera or an FX format camera.
This is because even if you are on a DX format camera now, you can use your FX lens on a DX format camera for now and still be able to use it if you upgrade to a FX format camera later on.
At the end of the day lenses tend to be more important than the camera body most of the time and lenses can last you an extremely long time, especially if they are high quality lenses that you take care of.
If you don’t have a big budget then just use DX lenses as they are much more affordable and if you are not doing anything on a professional level then these will be fine.
To be honest a lot of professional photographers do use DX lenses too.
We hope you found this article helpful!
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